Steam-boiler.



Patented Nov. 26, [90L w. n. McNAULL.

STEAM BOILER.

(Application filed Feb. 6, 1901.)

(No Model.)

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WILLIAM D. MONAULL, OF TOLEDO, OHIO.

STEAM-BOILER.

SPECIFICATION forming part of Letters Patent No. 687,255, dated November 26, 1901. Application filed February 6, 1901. Serial No. 46,241. (No model.)

- drawings.

This invention relates to steam-boilers of the kind known as vertical Water-tube boilers.

The objects of the invention are to produce a steam-boiler of the character named in which the top and bottom drums shall be secured by a strong tube passing through both drums and secured to the outer and inner drumheads, as well as by the tubes which connect the drums or headers of the boiler; also, to arrange the tubes with special relation to convenience of cleaning; also, to provide for the circulation of water in the boiler by an arrangement of the tubes such as will be explained.

Figure 1 is a vertical longitudinal section of the boiler, showing also the furnace and setting, not herein claimed. Fig. 2 isa crosssection of the boiler above the lower drum and below the upper drum, showing broken parts of the setting. Fig. 3- is a cross-sectional detail of upper T.

Theletter A indicates the boiler-casing,and B the furnace, which are of any proper construction to inclose the shell and direct the heat from the furnace between the watertubes at one side of the boiler, thence upward toward the upper drun1,and thence downward toward the uptake or chimney, as at O. The deflector is indicated in dotted lines at D, Fig. 1.

The numeral 1 indicates the lower drum. This is of suitable construction, being preferably a short cylinder with one arched and one flat end, the arched end being placed downward and provided with a suitable blow off 2.

The upper drum 10 is in general the same form as the lower drum, but may be either longer or shorter than the lower drum and has the arched end uppermost. A strong tube 4: extends from the lower head or end of drum 1 up into and through the drum 10. This tube 4 may approximate one-half or oneto the deflector D.

fourth of the diameter of the drums. erably tube 4 passes entirely through the upper drum 10, and both heads of this drum, as well as both heads of the lower drum, are firmly secured to this tube 4. At the bottom of tube 4 stays 5 are shown, which are riveted to the drumhead and tube and permit circulation of water between tube 4 and drum 1. At the upper end tube 4 has openings 6. to permit circulation to drum 10. The watertubes 6 6 connect the two flat faces of the drums 1 and 10 and are expanded into holes in these flat heads in usual manner. Manhole-plates, as 11, in the upper drum permit the entrance of these tubes 6 through the upper drum when necessary to replace a tube. Within tube 4 there is avertical tube 8 of considerably less diameter than tube 4, but preferably larger than tubes 6. The tube 8 is connected to elbows or Ts 9, which extend through the walls oftube 4 and open into the upper and lower drums. The feedpipe 12 enters the lower drum and opens into pipe 4-. The fire from furnace B enters between the water-tubes 6 and is deflected upward by the wall or deflector D. The heated products of combustion pass over deflector D and down between the tubes 6 on the other side of the deflector, and so to uptake O. The tubes 6 on the side of the boiler toward the furnace are arranged in rows at a right angle Thus a brush or steamblower can be passed in from the front of the furnace and made to enter between the passages between all the tubes 6 on that side of the deflector, and so the tubes can be cleaned pretty thoroughly. At the opposite side of the deflector D the tubes are arranged in rows parallel to the deflector, and as the boiler-setting has side openings or doors, of usual construction, for the entrance of a brush the tubes 60 can all be cleaned externally by the use of such a brush. Thus while the flame is not permitted to pass directly through the boiler from front to rear, but is deflected, the tubes are still quite readily accessible for cleaning. When the water enters from the feed-pipe, being naturally colder than the water in the boiler it would remain at the bottom, but is forced up inside tube 4 until it reaches the level of the upper T 9. Then by reason of difierence of specific grav- Prefity the cooler water flows down pipe 8 and out of the bottom T 9 into the lower drum. The intense heat applied to the surface of tubes 6 and 60 carries the water and steam upward through these tubes and into the upper drum. Should the tube 8 be insufficient for down circulation, the tube 4 then comes into play. Being much larger in diameter than tubes 0 and 60, the tendency is for the less-heated water to pass downward in this tube, and all the tubes 6 and being ex posed to intense heat causes an upward circulation of the water therein.

A very important feature of the construction of my boiler is the passage of tube 4: through the top and bottom drums and the securing of the same to the outer heads of these drums. This gives a strength to the structure which exceeds that of any similar boiler with which I am familiar. The tube dis a heavy tube, generally built up of boilerplate, and is of suiiicient strength to support a very great longitudinal strain. Consequently the drumheads are strengthened and the drums firmly tied together by this vertical tube 4:, to which all the drumheads are firmly attached by rivets or other usual securing means.

iVhat I claim is- 1. In a vertical water-tube boiler, the combination of an upper drum having a flat bottom and an arched top, a lower drum having a flat top and arched bottom, a series of water-tubes connecting the [lat faces of the two drums, and a single central water-tube secured to the inside of the arched face of the lower drum, passing through and secured to the flat faces of both drums, and extending through and above the arched top of the upper drum to which it is secured, said central tube having openings into both drums, substantially as described.

2. In an upright water-tube boiler as described,an upperand alower drum and water tubes connecting the proximate faces of the two, manholes in the upper head of the upper drum, so that tubes may be withdrawn or replaced through said drum by cutting and expansion, and a central water-tube extending through both drums and rigidly secured to the four heads of said drums, substantially as described.

3. In a boiler of the character described, the drums connected by water-tubes, the water-tube connected to the outer heads of the drums and extending through both drums, and an internal tube in said connecting-tube and having connection to both drums, substantially as described.

4:. In a boiler as described, the drums and tubes connecting them, and a deflector, the tubes between the deflector and furnace arranged in rows at a right angle to the deflector, the tubes at the back of the deflector arranged in rows across the furnace, substantially as described.

5. In a water-tube boiler, the top and bot tom drums, a central tube secured to both drums, and a deflector at each side of and extending from said central tube to the casing, all combined substantially as described.

6. In a steam-boiler as described the lower drum practically below the furnace-grate and. 

